Dynamic pattern transfer printing and pattern transfer sheets with spaced groups of trenches
Dynamic pattern transfer printing systems and method are provided, which decouple the design of the trench patterns on a source substrate for pattern transfer printing, from the resulting metallic paste lines patterns transferred to a receiving substrate, such as PV cells. The receiving substrate may be moved forward (along the scanning direction of the laser illumination used to transfer the paste from the trenches onto the receiving substrate) to reduce the pattern pitch with respect to the source substrate, and/or the receiving substrate may be moved backward (against the scanning direction) to increase the pattern pitch with respect to the source substrate. For example, dynamic pattern transfer printing may be used to accommodate different widths of the substrates for more effective pattern transfer, and/or to enable one-to-many pattern transfer technologies with high wafer throughput. Also, pattern transfer sheet with separate multiple groups of trenches are provided.
1. A dynamic pattern transfer printing system comprising:
at least one laser scanner configured to illuminate with at least one laser beam a source substrate that comprises a plurality of trenches arranged in a first pattern and holding printing paste, wherein the source substrate is configured to release the printing paste from the trenches and onto a receiving substrate upon the illumination by the laser beam,
a moveable stage supporting the receiving substrate, wherein the receiving substrate is affixed to the moveable stage during the releasing of the printing paste from the source substrate, and
a controller configured to control the laser beam illumination along the trenches, and at a scanning direction across the trenches, and further configured to move the moveable stage to yield a second pattern of deposited paste on the receiving substrate, which is different from the first pattern of trenches on the source substrate,
wherein the first pattern of trenches on the source substrate has a first pitch and the second pattern of deposited paste on the receiving substrate has a second pitch, and
wherein the controller is configured to move the moveable stage in at least one of:
along the scanning direction, to yield the second pattern on the receiving substrate, wherein the first pitch (p 1 ), the second pitch (p 2 ), a forward speed of the moveable stage (v F ) and a scanner speed across the trenches (v S ) are configured to have the relation p 2 =p 1 ·(v S −v F )/v S to make the second pitch smaller than the first pitch (p 2 <p 1 ); and/or
against the scanning direction, to yield the second pattern on the receiving substrate, wherein the first pitch (p 1 ), the second pitch (p 2 ), a backward speed of the moveable stage (v B ) and a scanner speed across the trenches (v S ) are configured to have the relation p 2 p 1 ·(v S +v B )/v S to make the second pitch larger than the first pitch (p 2 >p 1 ).
2. A dynamic pattern transfer printing system comprising:
at least one laser scanner configured to illuminate with at least one laser beam a source substrate that comprises a plurality of trenches arranged in a first pattern and holding printing paste, wherein the source substrate is configured to release the printing paste from the trenches and onto a receiving substrate upon the illumination by the laser beam,
a moveable stage supporting the receiving substrate, wherein the receiving substrate is affixed to the moveable stage during the releasing of the printing paste from the source substrate, and
a controller configured to control the laser beam illumination along the trenches, and at a scanning direction across the trenches, and further configured to move the moveable stage to yield a second pattern of deposited paste on the receiving substrate, which is different from the first pattern of trenches on the source substrate,
wherein the first pattern of trenches on the source substrate has a first pitch and the second pattern of deposited paste on the receiving substrate has a second pitch, and
wherein the controller is further configured to calculate the second pitch with respect to the first pitch, according to a relation between widths of the source substrate and the receiving substrate.
3. The dynamic pattern transfer printing system of claim 2 , wherein the first pitch is smaller than the second pitch and the controller is configured to move the moveable stage against the scanning direction at a backward speed set to convert the first pitch to the second pitch, and further configured to deposit paste from one source substrate onto a plurality of receiving substrates, wherein:
the first pattern of trenches on the source substrate comprises a plurality of groups of the trenches, and
the controller is further configured to deposit the paste from the trenches of each group onto one of the receiving substrates, and to switch the receiving substrate between consecutive groups of the trenches.
4. A dynamic pattern transfer printing method comprising:
illuminating a source substrate with at least one laser beam, wherein:
the source substrate comprises a plurality of trenches arranged in a first pattern and holding printing paste,
the source substrate is configured to release the printing paste from the trenches and onto a receiving substrate upon the illumination by the laser beam, and
the illuminating is carried out along the trenches, and at a scanning direction across the trenches; and
controllably moving the receiving substrate to yield a second pattern of deposited paste on the receiving substrate, which is different from the first pattern of trenches on the source substrate,
wherein the first pattern of trenches on the source substrate has a first pitch and the second pattern of deposited paste on the receiving substrate has a second pitch, and wherein the dynamic pattern transfer printing method further comprises at least one of:
moving the moveable stage in the scanning direction to yield the second pattern on the receiving substrate, and configuring the first pitch (p 1 ), the second pitch (p 2 ), a forward speed of the moveable stage (v F ) and a scanner speed across the trenches (v S ) to have the relation p 2 =p 1 ·(v S −v F )/v S to make the second pitch smaller than the first pitch (p 2 <p 1 ); and/or
moving the moveable stage against the scanning direction to yield the second pattern on the receiving substrate, and configuring the first pitch (p 1 ), the second pitch (p 2 ), a backward speed of the moveable stage (v B ) and a scanner speed across the trenches (v S ) to have the relation p 2 =p 1 ·(v S +v B )/v S to make the second pitch larger than the first pitch (p 2 >p 1 ).
5. The dynamic pattern transfer printing method of claim 4 , wherein the first pitch is larger than the second pitch (p 2 <p 1 ) and the controlled movement is carried out along the scanning direction at a forward speed set to convert the first pitch to the second pitch.
6. The dynamic pattern transfer printing method of claim 4 , wherein the first pitch is smaller than the second pitch (p 2 >p 1 ) and the controlled movement is carried out against the scanning direction at a backward speed set to convert the first pitch to the second pitch.
7. The dynamic pattern transfer printing method of claim 4 , further comprising calculating the second pitch with respect to the first pitch, according to a relation between widths of the source substrate and the receiving substrate.
8. The dynamic pattern transfer printing method of claim 6 , wherein the first pattern of trenches on the source substrate comprises a plurality of groups of the trenches, and the method further comprises:
depositing paste from one source substrate onto a plurality of receiving substrates by depositing the paste from the trenches of each group onto one of the receiving substrates, and switching the receiving substrate between consecutive groups of the trenches.
9. The dynamic pattern transfer printing method of claim 4 , carried out at least partly by at least one computer processor.
10. A computer program product comprising a non-transitory computer readable storage medium having computer readable program embodied therewith, the computer readable program configured to carry out the dynamic pattern transfer printing method of claim 4 , at least partly.
11. A pattern transfer sheet comprising:
a plurality of groups of trenches and configured to receive printing paste and release the printing paste from the trenches upon illumination by a laser beam onto a receiving substrate,
wherein a pitch of the trenches in each group is constant and the groups are separated by gaps, and
wherein the pitches in all groups are equal and are between 0.1-0.3 mm and wherein the gaps between all consecutive groups are equal and are between 1-10 mm, and the gaps correspond to a scanning speed of the pattern transfer sheet by a laser scanner optical head multiplied by a duration required to switch and position the receiving substrate between consecutive pattern transfers.